Drill.



dented Oct 31,1916.

mvmvr'ores R. U. HARRIS L-G. MOLIDOR.

DRILL.

APPLICATION HLED 1uLY14. 1914.

WITN ESS ICS:

, strong and durable construction.

UNITEDy sTATEs PATENT OEEIOE.

ROBERT U. HARRIS, OF WHITTIER, AND GEORGE MOLIDOR, OF FELLOWS, CALIFORNIA,

ASSIGNORS T0 ROTARY DISC BIT COMPANY, OF FELLOWSLCAIIIFORNIA, A CORPO- RATION OF CALIFORNIA.

To all wltom t may concern.'

Be it known that we, ROBERT U. HARRIS, of Whittier, in the 'county of Los Angeles and State of California, and GEORGE MOLI- DOR, of Fellows, in the county of Kern and State of California, citizens of the United States, have invented new and useful Im- ,provements in Drills, of which the follow- -ing is a specification.

This invention relates to rotary disk bit drills.

It is an object of the present invention to improve drills of the type involving rotary disk bits, whereby the bits may be readily mounted and dismounted, and which are of It is a further object of the present invention to provide a rotary disk bit drill in which the head or main member is made of j separable pieces which may .be securely and readily assembled and thereby permit the ready removal and renewal of parts.

l head 2 arespaced legs 9 which are so posi- The invention consists of the parts and the construction and combination of parts as hereinafter more fully described and claimed, having reference to the accompany- 'ing drawings, in which- 3 Figure 1 is an elevation of the bit, with parts inisection. Fig. 2 is a horizontal secltion onv the line -m, Fig. 1. Fig. 3 is a detail of one of the wearing plates or washers.

The present drillincludes a body or head, which is shown in Fig. 1 as formed with a substantially solid circular body 2, which 'is split'along the line 3 inV halves, although it is understood that the head 2 may be formed of one piece, if desired. When lar `5V for securing the halves together.

Above the threads 4 the' head is provided with tapering threads 6whereby the drill head may besuitably attached, as by a sleeve or collar 7 to a drill rod or tube 8. f

\Depending from the lower side of the tioned as to stand parallel to'each other and offset edgewise; the legs 9 being suiliciently 'separated to form a clearance space for intruded cutters. The legs 9 may be twisted diagonally relative to the' body of the head 2, or they may be forged in their proper relation without any twisting ofthe metal Specicationof Letters Patent.

DRILL.

Patented Oct. 31, 1916.

Application mea July 14, 1914. serial No. 851,001.

larly about transverse,screw-threaded holes 12, of which there is one in each leg. v

Insertible in the recesses or countersinks 11 are removable, reversible and intrchangeable washers 13, which are provided with apertures 14, Fig. 3, one of which is adapted to be passed over a stationary lug or projectlon 15 formed or provided in each recess 11.. These projections 15 serve the" function of preventing the washers 13 from rotating. Into each of the screw holes 12 there is screwed a substantial screw 16 fitting the threads of the screw hole 12; the smaller end of each screw being downturned and provided with threads 17 of a reverse pitch to the threads on the body ofy the screw.

Each screw 16 is provided` with a shoulder 18. adapted to bear' against the washer 13 and has a head 19,between"whic`h and the vwasher'l' there is mounted, upon the screw 16, a concavo-convex disk or cutter member 20. The cutter member 20 is provided with a rear central hub portion 21 adapted to bear upon the countersunk washer 13, there being a cutter -20 mounted on each leg 9, and of sufficient diameter to project beyond the edges of the legs so that when power is applied to rotate the cutter head 2 the cutters will engage and abrade the bottom surface of 4the drill hole.

In assembling a cutter 20, after a washer 13 has been adjusted in its recess 11 on oneA of the legs 9,the screw 16 is passed through the center bore of the cutter and vthescrew is lthen'adjusted in the screw hole 12 from the inner side of the leg, and tightened up, after which a lock-nut 17 is screwed up on the reverse threads 17 and locks the screw 16 firmly in position.

In manu cturing this type of bit, in

some sizes t e drill head 2 may be of one piece; the size of the'bod 2 and the relative offset position of the legs 9 being such as `to permit the ready mountingand dismounting of a pivot screw 16, withits cutter 20, upon the inside surface of one of the legs 9. In manufacturing small sized tools 110 of this type, however, it is desirable that the head 2 be made of two pieces which may be separated for the ready assembling and dismounting of the cutters on the inner surfaces of the legs 9.

To facilitate drilling operations, the drill body may be provided with suitable Water ducts 22 for the conveyance of water to the bottom of the well from any suitable source of supply connected vto the tube 8.

The disk 20 is thickened at its intermediate convex side and has an outer thin portion which will, While wearing away, keep a good cutting edge.

Having thus described our invention, what We claim and desire to secure by Letters Patent is- 1. In a rotary bit drill, a drill head having kspaced legs each having la threaded transverse opening therein, a pin projecting from each leg adjacent the opening therein, p

a washer plate provided with a central bore and a concentric series'of apertures which latter are to selectively engage with the pin of a leg for adjustment of the washer, a i

rotary cutter-having a bore of greater diameter than the bore of the washer, the bores of the cutter1 and washer being disposed in coincidence with each other and the threaded leg` opening, and a screw pin passing through the bores of the cutter and washer and threaded in the opening of the leg, said screw pin having a shoulder engaging with the washer and a head bearing against the cutter to retain the latter on the pin.

2. A drill including a head having spaced legs, concave-convex disks mounted for rotation relative to and connected to the legs, each of said disks having stepped annular reinforcing portions upon its convex face.

-In testimony whereof We 'have hereunto set our hands in `,the presence of two subscribing witnesses' ROBERT U. HARRIS. GEORGE MOLIDOR. Witnesses:

W. J. HOLLAND,

f R. T. JoNEs.i

W. J. HOLLAND, I. SMITH. 

